As we’ve explained, there’s no set way to conduct a rapid review. Rapid reviews involve a series of decisions about where to cut corners. Those decisions save time, but may also affect the breadth and integrity of your conclusions.
Below is a table with a quick summary of the typical shortcuts described and their potential consequences.
Potential shortcuts of a rapid review as compared to standard systematic review*
|Review Process||SR||RR||Consequence of RR shortcut|
|Searching||Comprehensive, several databases, few limits (e.g., language, date of publication)||Less comprehensive, fewer databases, more limits||Likely incomplete/potentially inaccurate picture of the evidence base. Less precise estimates (if doing meta-analysis)|
|Screening||Pre-defined eligibility criteria rigorously applied by 2 independent screeners. Conflict resolved through discussion or arbitration by a 3rd rater|
Pre-defined eligibility criteria applied by at least 1 screener
Staged screening of higher levels of evidence (based on study design, minimum number of participants, etc.)
Likely incomplete/potentially inaccurate picture of the evidence base. Potential bias and errors of single human screener not mitigated by a 2nd screener
Data from a comprehensive list of variables are extracted into well-defined, piloted data extraction forms by 2 independent extractors. Conflict resolved through discussion or arbitration by a 3rd rater
Data from a restricted list of variables (or large list but less detail) are extracted by a single reviewer
Likely incomplete/potentially inaccurate picture of the specific evidence within included studies. Potential bias and errors of single human extractor not mitigated by a 2nd extractor
Narrative synthesis and quantitative synthesis, where appropriate
Typically, narrative synthesis only
Synthesis may lack the depth and certainty of the findings of standard systematic reviews
Protocol: Registered with PROSPERO or published
Report: Published scientific paper
|Protocol and report: Often for internal purposes only, typically not registered or published|
Protocol: Limits transparency and accountability.
Report: Limits access to findings beyond commissioning stakeholders of review. Limits evaluating and testing rapid review methods
*Example methods are listed for comparison for both standard systematic review and rapid reviews; these are not meant to be definitive methods for either approach.